Why did Japan attack Pearl Harbor and not attack the Soviets instead?

Question

I have my own theories on this question, but I'm interested in seeing what other people think (preferably those who know a little about it or are willingly to do a little research).

As a reference point, consider this: many people know that Japan attack the U.S. because FDR cut them off from most of their oil supply with an embargo. The Japanese then made plans to take oil from Southeast Asia, which was then Dutch and British colonies. Therefore, taking those colonies meant certain war with America, so the plan was to attack the U.S. first and hope they didn't have the stomach to fight a long war in a far off land.

However, Siberia has a lot of oil as well. At that point in time, Germany was already at war with the USSR, so why didn't Japan simply attack the Soviets, thereby gaining the oil AND helping their supposed ally, Germany?

My personal opinion is that it had much to do with their war against China. What does everyone else think?

There have been a lot of good points here. I'd like to narrow the scope of discussion a bit.

I realize that the plans for war with the U.S. began before Germany invaded the USSR. However, by Dec. 7, 1941, the Germans and Soviets had been at war for almost 6 months. So why start a war with a non-belligerent nation when you could help an ally instead?

As far as resources in Siberia: oil WAS known to be there at the time. Stalin used forced labor to extract it. The oil would, obviously, have been much easier to extract in the Dutch East Indies. The only catch was war with the US.

The main question comes to this then: why did the Japanese not help the Germans by double-teaming the Soviets. They then could have (assuming their war in China was successful) focused on the Pacific from a position of greater power (as they would have had access to plenty of resources).
A good point was made on this regarding the attempt of the imperial army to provoke a war.

Answer 1

A number of good answers here.

Japan did attack the USSR in1938 and was beaten badly (losses 15000 to USSR 4000) and withdrew in1939. That Hitler had anything to do with it or that it was a coordinated effort is highly unlikely for Hitler wanted to pacify the USSR for his Polish campaign, and then again keep Stalin idle for his planned western campaign.

Japan realized that it's land military power was limited, even the Soviet troops were better equipped and when well lead superior to the Japanese. The region is vast an not too populated, extracting oil and resource from that area would have been beyond there capabilities at the time, Japan was looking for resources that could be immediately and easily exploited.

Japans "modern" military rested on the fleet and aircraft, there other weapons were poorly made, complicated, and not reliable. There supply and losgistic capabilities were terrible, or not equal to the capabilites of there combat troops. Japanese officers tended to purchase western made weapons over that of the Japanese issue, the Japanese side arm tended to fail or even discharge when the firing chamber was open.

After there lesson from the Soviets, the Japanese army learned to focus in areas and arenas that benefited there troops, and to avoid the open plains where tanks, and mobility had a deceive advantage. The army operated in Jungles, mountains, forests, areas that could be supported by either there air or sea assets.

Yamamoto's battle plan was to buy time, to hurt the Americans enough to give Japan 3 years to exploit there need resources and build up the fleet then to seek terms with the US. Hope that the US would be concern with things in Europe. By 1940 the German Army seemed undeatable, and it was hoped that once Britian fell the US would seek terms.

Yamamoto entered the war with the belief that Japan did not have a chance, he had to have known on December 8th 1941 that all his hopes were gone, Japan had lost the war.

A problem with studing history is that we tend to study things from the present to the past, putting bits and pieces into neat rows and boxes that appeear to make sense and give an impression that some person(s) knew what to do at the right time.

Answer 2

Because the Japanese already did a pre-emptive strike against imperial Russia back in 1905 and were familiar with the rapidity and success rates of Naval strike forces.

A land attack on the Soviet Union would not have been too stealthy, plus the Soviets had a fairly large standing army.

A Naval 'pre-emptive' strike against the U.S. forces at Pearl Harbor made strategic sense since most of the resources needed by Japan were only available through shipping lanes across the western pacific. A land strike against the soviets would have done nothing for those valuable shipping lanes for an island nation like Japan.

Answer 3

Actually its was more than just oil. That is thinking in today's ideas. Japan was resource poor but they had been cut off because of what happened in China. The US was pressuring Japan to withdraw. However, Japan also wanted to become an Imperial power, like many European powers and the USA. They understood that to expand their power into the Pacific would mean dealing with the biggest threat, the US Navy. Now, attaacking Russia will not help you deal with the US Navy which was the only power in the Pacific capibile of taking on the Japanese Navy which could have attacked the Japanese mainland.

Answer 4

First of all, Why would Japan fight against a very large soviet army when you can take out a battle fleet and make the islands in the Pacific Ocean ripe for the picking. I would choose the Pacific Fleet. And resources was the main reason for the Japanese to make a move. The US did place an embargo on Japan for not just oil but on SCRAP METAL as well. Also the biggest supply of oil, metal and rubber are in the Pacific. Also Siberia is not the place to tap into, It would be hard to cut off a place, Build a oil pump, and wait for oil. In the Dutch East Indies, The Europeans already did all the work and all they have to do is take it. Japan needs the resources to run its war machine and for its country to survive. Also the Pacific Fleet has been moved from San Diego to Pearl to be closer to the Pacific Island and a Threat to any Japanese move in the Pacific Ocean.
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Also The land of Siberia is hell, Stalin sent Political Prisoners to Siberia for Punishment. The place was not good for humans unless they can take it like the Eskimos. Also Its easier to take then to build in war. For oil to be transported from Siberia you have to build the infrastructure to transport it to ethier Korea or Eastern Russia that needs to be captured as well. Then changed it over to ships to Japan. With the DEI, all of the oil pipes to the harbors are built as well as the oil pumps. All they had to do is take the pumps, pipes, and the Harbor. Then pull their oil tankers up and dump the oil or refined oil into the hold and ship it to Japan. Also the Americans were more of a threat because the americans were calling for the Japanese to withdraw from its clam to China. Also their navy was great, but the japs needed to upgrade thier army including their weak armor. The M4 Sherman was the best tank in the Pacific Theater, and that was a medeum tank that was not good in the European theater. Also the Russians was dug in the border waiting for any jap to try and cross the line.

Answer 5

Several flaws here. One, Russia and Germany, at the time, were allies. Two, Siberia has a lot of oil, but at the time it was undeveloped. Look at the map, Siberia is huge, so big that it is barely inhbitable arctic wastesland. Until recent times the oil was not even know to be there. It is a vast waste land. Even now it is not economically feasible, yet.
Three. There was nothing to be gained. True the Soviets have a naval base on the Pacific but it was of no consequence.
Four. The Soviet Union was not a major power. WE shipped food and planes and ammunition to them to help them when Hitler turned on them.
Five. You have telescoped history. Not unusual in this day, but something to watch out for. What is today was not that way 65 years ago. A lot of major things have happened since then.
\Good question with good suppositions.
Pearl Harbor attack led to more then the Japs thought it would. They thought we would roll over and play dead and they could just do as they pleased. Today, that would be true, but not back then.

Maybe you could tell us the answer you want then we could give it to you. Mine was good others were better. Can you tell us exactly what you are looking for?

Answer 6

The Japanese Army wanted to go to war with the Soviet Union(the "strike north"), the Navy favored war with the US. (the "strike south.") Japanese Army forces in Manchuria tried to provoke a war with the Soviet Union in August of 1939 by crossing the border at Khalkin Gol. Unfortuantely for them, the Soviet commander in the area was Georgi Zhukov, their best general, and the Japanese were thouroughly trounced. Japan backed down, and that was pretty much the end for the strike north proponents. From this point on, all military planning was geared towards evential war with the US. In 1941, when Germany attacked, The Soviet Union kept strong forces in the east, expecting Japan to attack, until their spy in Tokyo, Richard Sorge, assured them that Japan was planning a strike against the US. The bulk of the Siberian force was then transferred to the defense of Moscow in time to win that battle.
If any Sovet Commander other than Zhukov had been at Khalkin Gol, things probably would have turned out quite differently.
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In hindsight, Japan probably should have helped Germany with the Soviet Union rather than attack the US,but because they had been preparing for the strike south for so long, the Army in Japan wasn't really equipped for such a fight. They were lacking in armor, and would have no means to rapidly advance across quite inhospitable terrain. Plus, until late October of '41, the Soviet forces in siberia were easily strong enough to defeat any attack, and the Japanese would have been sacrificing their army just to hold those divisions in the east. Remember also that until those divisions were unleashed on A.G. Center, no one outside the Soviet Union believed they had any chance of stopping the Germans anyway, and that was just days before Pearl Harbor. Japan would have had to commit to such a plan by October at the latest, and in October it certainly didn't look like Germany needed any help.

Answer 7

Japan needed Asia as it's "Iron Rice Bowl" - like the monopoly it had on Indonesia's rice crop in 1941 - Siberia may have oil but it doesn't have rice.

Answer 8

The Soviets weren't in the Pacific. This attack was based on naval power of Japan and the aim was to gain complete control on the Pacific.

Answer 9

Because the US had a massive fleet sitting in Pearl Harbor with the sole purpose of fighting Japan. The order haden't been given yet. But that's why there was a huge build up in Hawaii at the time.